CALL: DERIVATIVE
A 1-dimensional array of ordinates.
This array must be strictly in increasing order.
This array must have the same length as y.
A 1-dimensional array of function values.
This array must have the same length as x.
A number, the value of x at which y'(x) is to be computed.
On return, a number approximately equal to y'(x)
A character string that can contain the following
keywords:
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Keyword Meaning Notes
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LINEAR Linear interpolation Rarely useful
PARABOLIC Quadratic interpolation Default
CUBIC Cubic interpolation Risk of oscilation
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Keyword index.
Formatted on 10/11/98.